The present invention relates to a throw-in mat for a vehicle floor having a diamond-shaped groove pattern formed in a thermoplastic backing to prevent curling and bowing problems at extreme temperatures.
Throw-in mats are often provided in vehicles for protecting carpeted vehicle floors. These mats typically include nibs formed on the back of the mat to grip the carpeted floor. The nibs extend from a thermoplastic back which is secured to a primary backing layer, and a carpet pile is tufted (sewn) into the primary backing layer. Alternatively, the primary backing layer and thermoplastic back could be rubber components, but the thermoplastic material has a price and weight advantage over rubber.
However, if the primary backing layer and thermoplastic back comprise different thermoplastic materials or different configurations, then these components may have differing shrinkage rates at different temperatures. Accordingly, at extreme temperatures, the mat may curl or bow as a result of bending forces generated by the different shrinkage rates.
For example, at extremely cold temperatures, such as xe2x88x9230xc2x0 F., curling or bowing problems may arise if the shrinkage rate of the thermoplastic backing is greater than the shrinkage rate of the primary backing or carpet face material.
Accordingly, it is desirable to provide an improved throw-in mat design in which curling and bowing problems are alleviated at extreme temperatures without increasing the cost of the throw-in mat.
The present invention overcomes the above-referenced curling and bowing problems associated with the prior art throw-in mats by providing a throw-in mat including a thermoplastic back having a contiguous diamond-shaped pattern of grooves formed therein to prevent such bowing or curling.
More specifically, the present invention provides a throw-in mat for a vehicle floor including a primary backing layer having first and second sides with a carpet pile tufted into the first side of the primary backing layer. A thermoplastic back is secured to the second side of the primary backing layer. The thermoplastic back has a base thickness and a contiguous diamond-shaped pattern of grooves formed therein such that the thermoplastic back has a residual thickness adjacent each groove which is less than approximately 50% of the base thickness, thereby preventing curling and bowing problems at extreme temperatures.
Preferably, the residual thickness is approximately 25% of the base thickness, and the opposing tips of each diamond-shaped pattern have a tip radius of less than approximately 0.04xe2x80x3. Also, each groove of the groove pattern is preferably positioned at a groove angle of approximately 25xc2x0 to 28xc2x0 with respect to a pile direction of the carpet pile.
Accordingly, an object of the invention is to provide an improved throw-in mat design in which curling and bowing problems are alleviated at extreme temperatures.
The above objects and other objects, features, and advantages of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention when taken in connection with the accompanying drawings.